Bottom portion housing of a mobile device



FIG. 1 is a front view of a bottom portion housing of a mobile device showing our new design;

FIG. 2 is a rear view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a first side view thereof;

FIG. 6 is an opposite side view thereof; and,

FIG. 7 is a side-bottom-front perspective view thereof.

The portions rendered in broken line are not claimed. 

The ornamental design for a bottom portion housing of a mobile device, as shown and described. 